Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Zircons have been know since antiquity. The word zircon comes from Arabic and in turn from the Persian word zargun (zar=gold & gun=color) which is typical of the color of many gemmy zircons. Mindat currently lists 4425 localities for zircon (December 2013). There are undoubtedly many more. Zircon is found through out the earths crusts though usually in millimeter or sub-millimeter sizes. It commonly forms tetragonal prisms although sometimes the prism are short or entirely absent giving crystals consisting on only bipyramids. It is frequently found as well formed crystals and the habit of its crystals usually depends on the conditions of formation. In granite pegmatites they tend to be long and columnar and In alkaline pegmatites, short and pyramidal. Zircons display a broad range of colors; red, orange-red, orange, reddish-brown, yellow, gray, green, more rarely blue, and most rarely colorless. Colored zircons are often pleochroic, sometimes strongly so and the color is often zonal. The nature of their color is connected with electron-hole centers and ionic admixture: yellow – iron (Fe3+), red and light blue – uranium (U4+), green – zirconium (Zr4+) and also cadmium (Gd3+), thorium, hafnium.1 Australia provides almost 40% of the industrial demand for Zircon. This is supplied from the mining of sand deposits, usually from beach sands that are rich in tiny crystals of zircons whose origin is the weathering of zircon rich rocks. Zircons are usually easily separated from sand by gravimetric methods. Most of the demand for the mineral is for use as an opacifier in ceramics with some small part of zircon production diverted to make compounds of zirconium including zirconium oxide which is one of the most refractory materials know. 1.http://gems.minsoc.ru/eng/articles/zircon

Zircon crystals usually occur in sub millimeter size crystals in igneous rocks, but are also found in larger sizes, especially in pegmatites. The zircon variety called cyrtolite can form large clusters which typically show sub-parallel crystal forms. These can be up to 30 cm and probably larger. Zircons especially the cyrtolite variety contain uranium, thorium and rare earth elements. The decay of uranium and thorium in zircons, cause them, especially old ones, to be metamict. Because of this the properties of zircons vary considerably depending on how much of their crystalline structure has been destroyed by radiation (alpha particles). Zircons are sometimes classed as high, intermediate and low zircons which correlate to the amount of damage their internal structures have suffered. High zircons have a specific gravity of 4.65 to 4.71 which lowers to 3.04-4.10 in low zircons. The refractive index of high zircon is O=1.924 to 1.933 and E=1.983 down to 1.992 to n=1.78 to 1.84 for low zircon. The beneficence in high zircon is 0.058 to 0.059 and almost nothing in low, highly metamict zircons.22. Mineralogy for Amateurs, Sinkankas p.541.

Zircons are sometimes found in transparent crystals and make fine faceted gems of various colors which are often improved by heat treatments, some of which have been known from antiquity. The object of the heat treatments was to create more beautiful colors in the zircons and also often to create white colorless zircons which could be used as a diamond simulant. For may years, before the advent of cubic zirconia, moissanite and other man made diamond simulants, zircons were commonly used as a diamond substitute, hence there are countless thousands of small white zircons scattered around the world in jewelry. Jewelers have been taught to look downward through the tables of suspected zircons for the extreme birefringence of zircon which readily shows itself in the doubling of pavilion facets in the stone. The table of the stone is the big flat facet on the top and the pavilion is the pointed bottom of the stone. In zircons, the facet junctions of the pavilion facets will be doubled and it makes the stone look blurry. With a 10x loupe (a small magnifying glass) this property can be seen instantly. Most of them did not start life as white zircons but were yellow or some other color and were made white by heat treatment. Usually they were heated to about 1000 degrees centigrade and cooled slowly. Many of the exact heating methods were held as trade secrets by various families and companies engaged the diamond stimulant trade. White zircons almost always contain a fair amount of hafnium which replaces some of the zirconium in its structure. By heating the zircons, often the crystal structure becomes "annealed" and damaged parts of their structure are returned more nearly to their original state. This has the added benefit of increasing the refractive index of the stone and making it look more like a diamond. Other physical properties are also changed. The heating of metamict minerals is a technique often used when studying them. The yellow to red to brown varieties of zircon are sometimes called hyacinth but many other names have been given to various colors of zircons. The American Museum of Natural History in New York City has a perfect blue-green faceted zircon of 208 ct.44. http://gems.minsoc.ru/eng/articles/zircon/

Zircons have become important to geologists for their role in studying and understanding the geological processes that have shaped the earth. This is because of the high melting point of zircon which is about 2500 degrees centigrade; they have great resistivity to chemical attack and toughness in standing up to erosional forces. Below are comments by Peter Nancarrow that illustrate these properties.

"Zircon is considered by many people to be perhaps the most durable and long lasting of all the minerals found in the earths crust. "Weathering" covers a variety of decomposition processes, including water solution, acid rain attack, organic processes (e.g. action of products of leaf decay, lichen digestion etc.) freeze/thaw, solar heating etc, and a mineral that is resistant to one or other or even any chemical attack, may not be resistant to a mechanical process such as rapid thermal expansion. I am not considering brittleness or abrasion resistance here; the effects on particles of being ground about by a glacier or between boulders in a scree, being rolled along a stream bed, or washed about on a beach are not weathering processes sensu stricto; those processes come under the heading "erosion" rather than "weathering". The latter is defined as "The process by which rocks are broken down and decomposed by the action of external agencies such as wind, rain, temperature changes, plants, and bacteria. An essential feature of the process is that it affects rocks in situ; no transportation is involved. This is the factor which distinguishes it clearly from erosion." (Whiten & Brooks, 1972).

I am reminded of the occasion when I was working in the X-ray analysis section of a geochemical laboratory and one of our analysts brought me a specimen to be identified. He had been trying to get a sample of granite into solution for a whole-rock analysis, to include those elements which could not be measured by XRF, particularly Be & Li, but he was left with a small residue of fine sandy pink material in the bottom a test tube which he had been unable to dissolve, even in super heated concentrated HF! (Using a Teflon "bomb" in a high-pressure autoclave). Everything else, all the quartz, topaz, tourmaline, cassiterite etc., was gone. Under the microscope I could see that the sample consisted of lustrous tetragonal crystals with absolutely no indication of even the first stages of solvent attack; they had sharp-pointed terminations and crystal edges and bright lustrous faces with no etching features. The only pitting could be attributed to the solution of what had been exposed inclusions embedded in the crystal faces, but even these apparent weaknesses in the integrity of the crystal surfaces had not let one of the most corrosive of acids do its work. Yes, you guessed right; that concentrate consisted of zircon, and nothing but zircon!

So, all those factors considered, I would certainly have to agree that my vote for the mineral "most resistant to weathering" would certainly be for zircon. With regards to its subsequent resistance to erosive processes, it's pretty hard, (Mohs 71/2) and not particularly brittle either; I just put a zircon crystal on an anvil and hit it several times with a hammer! It took a rather harder blow to crack it than would be required for a similarly sized quartz crystal."

Because of zircon often contains uranium and thorium due to their ability to survive geological processes they have become important to scientists trying to unravel and study the history of the earth. They are particularly suitable for age dating using uranium-lead (U-Pb), fission-track, and U+Th/He techniques. Oxygen isotope studies of some zircons give indications that there may have been water on the surface of the earth as far back as 4.4 billion years ago although there is still debate about this.2,32. Wilde S.A., Valley J.W., Peck W.H. and Graham C.M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago". Nature 409 (6817): 175–8.3. Wilde S.A., Valley J.W., Peck W.H. and Graham C.M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago". Nature 409 (6817): 175–8.

You ultimately will decide which localities produce the best specimens. But I think it possible to speak kind words about the quality of specimens from four localities and would direct your attention those exampled above. Although there is not one from the wonderful Mud Tank, Australian locality, they are a bit rough for my taste, I would love to have one of these giants in my collection but alas I am still waiting to find one. Many tiny crystals of zircons are so perfect and wonderful that I could not but include many photos of them in this article. Those who may revise this article in the years to come may have a different viewpoint and may not include as many. I have also included a rather large selection of tiny French alluvial zircons that have been collected by a few dedicated individuals who are passionate about them. They are mostly each from different streams, rivers, beaches and a pond. No one know for certain where they were formed except in a general sense. Somewhere up stream or river is the only logical answer. I have included them on a whim and hope you enjoy them too.

There are two principal localities in Brazil that have produced substantial quantities of zircons about which collectors can speak kindly. Those are the Peixe alkaline complex in Tocantins, Brazil and the other is the Poços de Caldas alkaline complex in Minas Gerais.

Dear Rock,there is the single zircon locality - zircon point on Vavnbed Mt. So You had subdivide specimens from the same locality on two groups - with complete and incomplete labels. :)Kind regards,Pavel

The area name of "Langesundsfjorden, Porsgrunn, Telemark, Norway" would better be simply stated as "Langesundsfjorden area, Norway". Langesundsfjorden is a fjord which partly divides the two counties of Vestfold and Telemark, and the pegmatites are found distributed throughout the area. Porsgrunn is simply a town in south Telemark.

Thanks guys. Already I can see the article getting better. The zircon entry like many others I put there to act as a place marker and a lighting rod to try and locate someone interested enough in zircons to take it upon themselves to write the article and select the pictures for the article. I am pretty sure that there is someone out there who could do a better job on the article than I. I started writing these articles some years ago and arbitrarily decided to start with the minerals starting with A. I wrote a few hundred pages about them and as I went along, my ideas about what should be included and not included (not to be included became less and less) underwent a lot of changes so by the time I came to the end of all the A minerals in Fleischer's, I needed to go back and make changes in most of what I had written. Then I got the idea that all this should be transfered to a Wikipedia type project because it became obvious that just one or even a few people could not do the job very well. Once on mindat, the project has been further changing because of the ability to import images easily and the ideas and suggestions of others. We will just have to keep working and see where the project goes. The more articles that are written and the more contributions that are made, the stronger and more useful and authoritative it will become. Perhaps in ten or twenty years it will become something really good and useful.

The photo from Rob Lavinsky said to be "zircon crystals altering to eudialyte" from Kangerdluarssuq in Greenland looks like a photo of ordinary eudialyte crystals from the area. Zircon is very resistent to weathering and geochemical alterations and I cannot rember seeing any pseudomorphs after zircon crystals - let alone "zircon altering to eudialyte". There are zircons in the Ilimaussaq complex and also at Narssarsuk in Greenland, but I have never seen any large or spectacular crystals or specimens.

The listing of a photo of zircon under the heading of "Kåfjord copper mines" is also misleading as the text of the photo clearly states that it is from the island of Seiland.

Knut,Thanks for the heads up. When the article gets written we will probably not include those images. The links listed were just grabed in haste from the gallery without much thought applied to them. Often when creating the article some of the images are thrown out and or others added. Then of course the help we get in the threads like yours are invaluable in helping I and the other authors stay out of trouble. Would you like to work on an article here? Like perhaps Zircon, this mineral? I would be only too glad to turn it over to you. What is above is just a place holder rather than the start of an article.

- Peixe alkhaline complex, Tocantins state (I am not sure about Natividade, Peixe alkhaline complex; I will check if Natividade is the right name of the city where the alkhaline complex is located)

- Poços (should be pronounced "possos") de Caldas, Minas Gerais - it is also a big alkhaline complex

All others are 100% wrong; it is crazy, some are coimpletely absurd, like Sapucaia mine, Campos Verdes de Goiás and Brumado; all these specimens came from Peixe; Poços de Caldas complex was mined from the 1940's until the late 1980's for zirconium ore but now all mines are closed.

Some more Canadian localities that have produced high-quality zircon crystal specimens are: Smart mine, Lake Clear, Renfrew Co., Ontario (we have one poor photo used in the article) Turner's Island, Lake Clear, Renfrew Co., Ontario (we have no images of zircons from this locality) Kuehl Lake, Brudenell Twp., Renfrew Co., Ontario (we have one OK photo) McLaren mine, Otty Lake, Lanark Co., Ontario (we have one so so photo used in the article) Silver Queen mine, Murphy's Point, Lanark Co., Ontario (we have no images at all for this locality) Seybold mine, Wilson's Corners, Quebec (we have no images of zircons from this locality) Saranac mine, Tory Hill, Ontario (we have used two images of zircons from this locality in the article) Mathilda Lake, Harrington, Argenteuil Co., Quebec (we have no pictures of zircons from this locality)

Also, from New York State: Natural Bridge, (Diana), Lewis County (we have one zircon pictured in the article, but it is not outstanding) Rossie, St. Lawrence County (We have no images of zircons from this locality) Various pegmatites, Bedford, Westchester Co. (we have pictures of a few zircons from Bedford, but they are pretty nasty looking things and I am not sure we should include them in the Best Minerals article. Scott Farm, Fine, St. Lawrence Co. (we have no images of zircons from this locality.)

David,You are correct. I have fixed it. I can't believe you clicked on all those links to see the pictures in that stub of an article. I will have to make zircon my next Best Minerals article to work on. Sometimes it is daunting to contemplate the vast amount of work that yet needs to be done. But I am starting to come to terms with what it is like to be working on a project that can never be finished.